Dissociation-Enhanced Lanthanide Fluorescent Immunoassay

For Robust, High-Performance Time-Resolved Fluorescence (TRF) Assays

Utilizing the DELFIA (Dissociation-Enhanced Lanthanide Fluorescent Immunoassay) platform’s unique chemical properties of lanthanide chelates in concert with time-resolved fluorescence (TRF) detection, BioAgilytix is able to develop assays that offer high sensitivity, wide dynamic range, superior stability, and excellent flexibility.

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DELFIA is a heterogeneous, time-resolved fluorescence (TRF) assay method that detects reagents labeled with lanthanide chelates containing Europium (Eu), Terbium (Tb) or Samarium (Sm). Depending on the analyte and antibodies, as well as the required level of sensitivity and dynamic range, these lanthanide-labeled immunoreagents can be applied in non-competitive (sandwich-type) or competitive TRF assays. DELFIA assays are performed on 96- or 384-well formats, using an antibody coated plate to capture target analytes in a sample.

A DELFIA assay is virtually identical to that of a standard sandwich ELISA, with the analyte first captured on the coated microplate, and the detection antibody added to complete the sandwich. But unlike ELISA, a lanthanide chelate-labeled detection antibody is used, and an enhancement step unique to DELFIA releases the lanthanide from the antibody complex, producing a new, highly fluorescent lanthanide chelate contained within a protective micelle.

The highly fluorescent lanthanide chelates yielded possess properties that enable delayed signal measurement at a wavelength that provides for little background interference for superior detection sensitivity via time-resolved fluorometry.